• International Journal of Industrial Entomology and Biomaterials
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• v.8 no.1
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• pp.81-87
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• 2004

In order to investigate the effects of supplementary nutrients on silkworms, Bombyx mori, an experiment was conducted with ascorbic acid treatments. Dietary supplements of ascorbic acid 1, 2 and 3% were fed to silkworm larvae through 1st to 5th instar, The larvae were fed by mulberry loaves of Kokoso variety and the supplementary loaves were used once a day. These treatments resulted in a significant increase of biological parameters such as larval weight, the rate of food consumption and the approximate digestibility of the food. But the economical parameters such as cocoon weight and cocoon shell weight didnt show considerable difference compared to control. Dietary supplement of 2% ascorbic acid increased the larval weight by 7.8% and reached to 1.065g, which had the highest weight increase in the fourth day of 4th instar larvae. The percentage of daily weight increase in this group of larvae (79.01%) had significant difference compared with other treatments. The nutritional efficiency index in this group of larvae was better than others. Also the abundance of biochemical macromolecules such as glucose, cholesterol, triacylglycerol and urea in haemolymph of larvae fed by 2% ascorbic acid increased to become 29.75 (mg/㎗), 24 (mg/㎗), 75.4(mg/㎗) and 32.1(mg/㎗) respectively. But protein contents of haemolymph of larvae in each treatment were not significantly different. Since all the results achieved were not considerable either statistically or economically, this method could not be recommended to improve the sericultural parameters.

• Parasites, Hosts and Diseases
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• v.49 no.4
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• pp.445-448
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• 2011

A survey was performed to find out the intermediate hosts of Gnathostoma nipponicum in Jeju-do (Province), the Republic of Korea. In August 2009 and 2010, a total of 82 tadpoles, 23 black-spotted pond frogs (Rana nigromaculata), 7 tiger keelback snakes (Rhabdophis tigrinus tigrinus), 6 red-tongue viper snakes (Agkistrodon ussuriensis), and 2 cat snakes (Elaphe dione) were collected in Jeju-do and examined by the pepsin-HCl digestion method. Total 5 gnathostome larvae were detected in 3 (50%) of 6 A. ussuriensis, 70 larvae in 3 of 7 (42.9%) R. tigrinus tigrinus, and 2 larvae in 2 of 82 (8.7%) frogs. No gnathostome larvae were detected in tadpoles and cat snakes. The larvae detected were a single species, and $2.17{\times}0.22mm$ in average size. They had characteristic head bulbs, muscular esophagus, and 4 cervical sacs. Three rows of hooklets were arranged in the head bulbs, and the number of hooklets in each row was 29, 33, and 36 posteriorly. All these characters were consistent with the advanced third-stage larvae of G. nipponicum. It has been first confirmed in Jeju-do that R. nigromaculata, A. ussuriensis, and R. tigrinus tigrinus play a role for intermediate and/or paratenic hosts for G. nipponicum.

• Korean Journal of Veterinary Research
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• v.39 no.3
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• pp.602-608
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• 1999

Two-day old house fly adults were exposed to six insect growth regulators, flufenoxuron, teflubenzuron, triflumuron, diflubenzuron, methoxyfenozide, tebufenozide, as a feed additive (milk+5% sugar+chemical) in the laboratory for 6 days. The number of eggs deposited by the exposed-adults, viability of the eggs, and $F_1$ larval development were checked. All the IGRs tested were found to have no adverse effect on the reproduction of house fly, except methoxyfenozide (210ppm). The most effective inhibitor to egg hatch was flufenoxuron, followed by teflubenzuron, triflumuron, and diflubenzuron. Exposure to flufenoxuron (over 5ppm), teflubenzuron (over 25ppm), triflumuron (over 125ppm), and diflubenzuron (over 125ppm) reduced egg hatchability to 0 to 1.3%, but lower concentrations of these IGRs were less effective (6.3 to 46.3% egg hatchability). Almost all the larvae emerged from eggs deposited by the adults exposed to diflubenzuron (62.5ppm) and teflubenzuron (12.5ppm) failed to develop into pupae, causing total mortalities of 98% and 100%, respectively. However, two IGRs, methoxyfenozide and tebufenozide, did not inhibit egg hatch and $F_1$ larval development, except methoxyfenozide (210ppm) treatment These results suggest that these 4 IGRs may be used in the development of autosterilization system for house fly control. However, further work is required to develop delivery systems capable of transferring an effective dose to the fly under field conditions.

• The Korean Journal of Zoology
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• v.36 no.3
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• pp.373-379
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• 1993

The heat shock protein (HSP) genes are expressed at various stages of the Drosophila life cycle even under non-heat-shock conditions. In the present study, developmental changes of HSP23 gene expression and the role of 20-hydroxyecdysone (2OHE) on the HSP23 gene expression were investigated in Drosophila melanogaster. The Northern blot and Western blot analyses showed that HSP23 gene expression occurred at the early third instar larval stage, reached the highest with a sharp peak in the white prepupa, and then decreased throughout the pupal period. When the HSP23 gene expression was compared with the secretion of 20HE, there is a slmiladty between 20HE synthesis and HSP23 gene expression during the third instar larval-prepupal period. It appears that 2OHE regulates expression of HSP23 gene at larva-pupa molting period, and that, 2OHE is also involved in the control the metamorphosis in some part through the HSP23.

• Korean Journal of Environmental Biology
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• v.38 no.4
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• pp.625-633
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• 2020

The effects of temperature and salinity on egg development and settlement of the ascidian Herdmania momus were investigated. Adult specimens were collected from the Dodu Yacht facility in Jeju Island, Korea(33°30'30.54"N, 126°27'55.46"E) in August 2018. Egg development and larval settlement were observed and recorded at 8 h intervals using a stereomicroscope, under nine temperature (10, 13, 16, 19, 22, 25, 28, 31, and 34℃), and four salinity regimens (28, 30, 32, and 34 psu). The highest hatching rate (82.8±7%) was observed at 32 psu and 25℃ and the lowest hatching rate (1.0±2%) was at 34 psu and 13℃. The developmental rate (0.222±0.0994) was highest at 28 psu and 28℃, and lowest (0.016±0.008) at 30 psu and 13℃. The highest settlement success rate (77.1±5%) was at 32psu and 25℃ and the lowest(0.1±1.0%) was at 30psu, and 13℃. The rate of settlement(0.080±0.000) was highest at 28psu and 28℃, and lowest(0.013±0.000) at 30psu and 13℃. Both hatching and settlement success rates increased as temperature increased and tended to decrease beyond an optimal temperature range. Herdmania momus preferred 30-34 psu salinity and 22-25℃ temperature. This study provides baseline information about the life history of H. momus, and important data to control the damage caused by the increase in number and distribution of this invasive ascidian.

• Animal cells and systems
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• v.14 no.1
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• pp.25-30
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• 2010

We employed a new and improved differential display reverse transcription-polymerase chain reaction (DDRT-PCR) method, which involves annealing control primers (ACPs), to identify the genes that are specifically or prominently expressed in olive flounder (Paralichthys olivaceus) juveniles (35 days post-hatch; dph) compared to larval-stage (dph 21) flounder. Using 60 ACPs, we identified eight differentially expressed genes (DEGs) and basic local alignment search tool (BLAST) searches revealed eight known genes. Gene expression levels were confirmed by RT-PCR. Phosphoglucose isomerase (PGI) was highly expressed at 21 dph, while nephrosin, myosin light chain (MLC), myosin heavy chain (MHC), carboxypeptidase A, chymotrypsin B, fish-egg protein, and matrix protein were expressed at 35 dph. PGI, MLC, and MHC expression was further analyzed by RT-PCR. The differentially expressed genes identified in this study may provide insights into the molecular basis of development in olive flounder.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.1
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• pp.123-127
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• 2012

An experiment was carried out to boost the production of tasar crops through application of secondary nutrients. Different combinations of secondary nutrients were prepared and its effect was studied on the yield and quality of leaves of tasar food plant Terminalia tomentosa W & A with 2.4 m ${\times}$ 2.4 m spacing and cocoon characters of tasar silkworm Antheraea mylitta Drury reared on them. Among different combinations of secondary nutrients, foliar application of magnesium sulphate (2%, w/v) and basal application of 3 quintal/ha of calcium carbonate (secondary nutrient combination SM5) was found to be the best in crop improvement. It improves the quantity and quality of leaves as well as the commercial characters of cocoons. As a result, silk production improves. Under this combination, leaf yield increased by 26.55% in comparison to control. Average increase in moisture, total mineral, crude protein and total carbohydrate was 3.26%, 20.84%, 15.39% and 17.85% respectively as compared with control. Further, bio assay studies revealed that average larval weight, E.R.R., cocoon weight, shell weight and silk ratio percent increased by 11.25%, 25.71%, 20.05%, 35.14% and 12.17% respectively over control which indicates that secondary nutrient combination $SM_5$ has significant role in improving the production of tasar crops.

• International Journal of Industrial Entomology and Biomaterials
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• v.25 no.1
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• pp.111-114
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• 2012

In previous studies we have shown that a sw17255 gene was expressed in hemocyte-specific tissues of the silkworm, Bombyx mori L. (Lepidoptera: Bombycidae). It was verified that the sw17255 core promoter region contains elements that regulate the expression of this gene in hemocyte tissue; the selected promoter region spans nucleotides -1 to -2,112 upstream of the start codon. Each of the luciferase reporter gene expression vectors under the control of 4 different kinds of promoter candidates, (-2,112/-1), (-1,640/-1), (-1,169/-1) and (-579/-1), and the control reporter plasmid DNA, were introduced into B. mori larval coelom by direct injection using a syringe. The promoter candidate [E] (-579/-1) showed more than 1.67 fold transcriptional activity compared to control promoter activity. Higher productivity of an expressed gene in the transgenic silkworm by this promoter combination could be achieved in the near future. The foreign recombinant protein could be easily harvested from the blood of the transgenic silkworm.

• Korean journal of applied entomology
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• v.40 no.2
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• pp.137-141
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• 2001

This experiment was conducted to investigate the control effect of nuclear polyhedrosis virus and NeemAzal-T/S on Spodoptera litura larvae. In laboratory test, values of$ LT_{50}$ and $LT_{95}$ when treated with S. litura nuclear polyhedrosis virus (SINPV) $1$\times$10^{8}$ PIBs/ml plus NeemAzal-T/S 200 ppm were 1.94 and 8.33 days, respectively. Control effect of the combination of SINPV $1$\times$10^{8}$ plus NeemAzal-T/S 200 ppm was higher than the other concentrations. This mixed treatment could reduce LT$_{95}$ by 3 days. When SINPV alone was sprayed to the S. litura larvae reared on chinese cabbage seedling, the mortalities were 10.7~6.7% at 4 days after treatment. In combinations of SINPV plus NeemAzal-T/S at each level of concentration, the mortalities appeared faster and higher at 4 days after application than single treatment. Especially, the mortalities by combinations of SINPV $1$\times$10^{8}$ /PIBs/ml plus NeemAzal-T/S at 75~200 ppm were 100% at 9 days after treatment. The body weight of untreated larvae was increased 9.4-folds from 235 mg to 2194 mg after 7 days. However, the increasing levels of larval weight were 4.8- and 7.0-folds in the separate treatments of NeemAzal-T/S and SINPV, respectively. Whereas in the combinations of SINPV $10^{4~8}$ PIBs/ml plus NeemAzal-T/S 75~200 ppm, larval weight was increased 3.9 to 2.9-folds. These results showed that the mortality and inhibition of larval weight in the combination of SINPV and NeemAzal-T/S were highly enforced by synergistic effect.

• Journal of Life Science
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• v.30 no.10
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• pp.860-866
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• 2020

This study examined the characteristics of eggs obtained from layer chickens reared with feed that included Tenebrio molitor larvae, which were in turn bred using feed that included dried food waste powder. The eggs showed a tendency to be slightly thinner in the treated groups, but the Haugh unit indicating freshness was higher in the treated groups than the control group, and the 5% larval-treated group showed the highest value. The color of the yolk tended toward higher redness, lower brightness, and lower yellowness in the 5%-treated group, which also showed similar crude fat and protein values to the control group; the 10%- and 15% larval-treated groups had lower crude fat and protein values, although the carbohydrate content was higher. Structural amino acids in the treated groups showed a higher ratio of non-essential amino acids to essential amino acids than the control. The polyphenol content, which is an index of antioxidants, was highest in the 5%-treated group, and it is thought that this may affect the storage and antioxidant properties of the eggs. Thus, when employed with a feed source to maintain high protein and high fat, T. molitor larvae may cause critical changes in the nutrient content of eggs and improve their freshness.